Fluid pressure responsive inclinometer



Jan. 16, 1962 F. s. KIELMAN, JR 3,

FLUID PRESSURE RESPONSIVE INCLINOMETER Filed May 11, 1959 3 Sheets-Sheet 1 32 24 2O 94 2Q 24 32 24 20 94 2O 24 FIG. I. FIG. 2.

INVENTOR. FRED S. KIELMAN, Jr.

ATTORNEYS Jan. 16, 1962 F. s. KIELMAN, JR

FLUID PRESSURE RESPONSIVE INCLINOMETER 3 Sheets-Sheet 2 Filed May 11, 1959 m w W M m iw ///Z/ 6 "f a a #3; n mmmw ammm aw m nawwuwu FIG. 3.

FIG. 4.

INVENTOR.

FRED S. KIELMAN, Jr.

ATTO RN EYS Jan. 16, 1962 F. s. KIELMAN, JR 3,016,621

FLUID PRESSURE RESPONSIVE INCLINOMETER Filed May 11, 1959 3 Sheets-Sheet 3 INVENTOR.

FRED S. KIELMAN, Jr. BY v ATTOR NEYS trite States aten t' entrain Patented .Fan. 16, 1962 3,016,621 FLUID PRESSURE RESPONSIVE INQLINGMETER Fred S. Kielman, .lr., Houston, Tex, assignor to Sperry- Sun Well Surveying Company, Philadelphia, Pa., a corporation of Delaware Filed May 11, 1959, Ser. No. 812,246 9 Claims. (Cl. 33-265) This invention relates to a fluid pressure responsive inclinometer and, more particularly, to apparatus responsive to fluid pressure in a bore hole for providing a fluid pressure indication at the surface of the earth when the angle of the bore hole exceeds a predetermined inclination from vertical.

In the drilling of bore holes there is commonly employed a circulatory flow of mud, air or gas which is generally pumped downwardly through the drill stem and flows upwardly around the drill stem carrying cuttings out of the bore hole as the drilling proceeds. During the course of such drilling it is not uncommon for the direction of drilling to deviate from vertical. It is therefore desirable to incorporate in the drilling apparatus means by which an indication may be provided when the angle of drilling exceeds a predetermined deviation from vertical.

It is the primary object of this invention to provide apparatus which may be located in a drill string preferably attached to the lower end thereof in the immediate vicinity of a drill bit and which will not interfere with the normal uninterrupted drilling operation and the normal circulation of the drilling fluid but which, upon interruption and re-establishment of drilling fluid, is actuated by the circulating fluid, which may be mud, air or gas, to block the flow of drilling fluid thus providing at the surface of the earth an indication. While the apparatus disclosed herein is particularly adapted for use with air or gas, the principles involved therein may equally well incorporate apparatus operated by a liquid fluid flow.

It is a further object of the invention to provide a fluid flow responsive inclinometer which will act as a check valve preventing reverse flow of fluid upwardly through the drill string.

It is a further object of the invention to provide a flow responsive inclinometer which, after operating to provide an indication, may be reconditioned without removal from the bore hole in order that drilling may proceed with unrestricted fluid flow through the drill string.

These and other objects of the invention relating particularly to details of construction thereof will be evident from the following description when read in conjunction with the accompanying drawings in which:

FIGURE 1 is an axial section through the apparatus with the parts thereof shown in normal position prior to operation;

FIGURE 2 is an axial section through the apparatus showing the parts in the positions which they will occupy when the apparatus is operated while in a position of inclination less than a predetermined degree;

FIGURE 3 is an axial section through the apparatus showing the parts in the indication producing positions which they will occupy when the apparatus is operated while in a position of inclination exceeding a predetermined degree;

FIGURE 4 is an axial section through the apparatus showing the parts in the positions which they will occupy when fluid pressure in the drill string above the apparatus has been relieved after the apparatus has been operated in the position shown in FIGURE 3;

FIGURE 5 is a fragmentary showing of parts of the apparatus occupying possible specific relative positions; and

FIGURE 6 is an axial section: through. a modified form of apparatus particularly useful when the drilling fluid is: a liquid.

In FIGURES l-4- there is shown generally at 10 inclinometer apparatus adapted to be positioned within a drill string in the vicinity of the drill bit. The apparatus includes a casing 12 provided with an O-ring 14 positioned in an external circumferentially extending slot for providing a seal between the casing and the internal wall of the drill pipe, the casing being adapted to rest on an internal stop within the drill string which positions it adjacent to, but above the bit.

The internal cylindrical wall 16 of the casing is provided at its upper end with an inwardly extending circumferential abutment forming a radially extending shoulder 18. Longitudinally extending grooves 26 are formed in the inside wall 16 of the casing having their upper and lower ends terminating as indicated at 22 and 24, respectively.

A sleeve 26 is fixed within the casing by means of a locking snap ring 28 and has its upper and lower ends 30 and 32, respectively, terminating below and above the upper and lower ends 22-24, respectively, of the passages 20.

A piston 34 is slidably positioned within the sleeve 26 and has its upper end extending above the upper end 30 of the sleeve 26 provided with an outwardly extending radial flange 36. The flange 36 is in sliding relationship with the inside wall 16 of the casing 12 above the upper ends 22 of the grooves 20 therein. The upper surface of the radial flange 36 is adapted to engage the radial surface 18 of the casing 12 and is urged into this position by means of a spring 38 acting between the lower end of the piston 34 and a plug member 40 positioned in the lower end of the sleeve 26 by means of a pair of snap rings 42. The member 40 is provided with a circumferentially extending groove retaining an O -ring 44 providing a seal between the member 40 and the sleeve 26.

The piston 34 is provided with a bore 48 within which is positioned a sleeve 46 supported therein by a snap ring 50 and supporting a disc 52 provided with a central bore within which is supported a ball race and balls 54.

A pendulum 56 having a bluntly pointed lower end 58 has a member 57 extending upwardly from the upper end thereof terminating in a ball 58 adapted to rest on the ball race 54 and be pendulously supported thereby.

A member 62 is located above the disc 52 and in radial openings therein there. are slidably mounted detent pins 64 urged inwardly by an O-ring 66 located in an annular groove in member 62.

A sleeve 68 is positioned on the disc 62 and positions a disc 70 which has ears extending between the sleeve 68 and a shoulder 72 formed in the wall of the piston bore 48. A bellows 74 has its lower end sealed to the disc 70 and its upper end sealed to a disc 76 aflixed to the top 78 of an inverted cup having downwardly extending side walls 80 loosely embracing the ears of disc 70 and having a bar 82 afl'ixed to and extending between opposite sides of its rim. A plug 84 is aflixed to the central portion of the bar 82 and enters a central bore in the member 62. The elements just described are loose fitting so that the exterior of the bellows is exposed to the pressure existing below the piston 34.

The member 40 provides a housing for a pendulum limit sleeve 86 slidably positioned in the bore extending longitudinally therethrough and urged upwardly therein by a spring 88 to the upward limit determined by the engagement of a radially extending outward flange 90 with a radial shoulder 92 formed in the bore in the member 4-0. The opposite end of the spring 88 acts against a plug 94 secured in the bore of the member 40 by means of a snap ring 96. An Q-ring 98 is provided in a groove in the plug 94 in order to provide a seal between the plug 94 and the wall of the bore in the member 40.

The space within the sleeve 26 between the member 40 and the piston 34 is partially filled with oil to a level as indicated at 27.

The upper surface of the sleeve 86 is formed with an internal conical bevel 100. The upper surface of the member 40 is formed with an annular V-shaped groove 102 having its surface formation such as to substantially mate with the pointed end 58 of the pendulum 56 as will be evident from FIGURE 3. The base of the groove 102 is provided with an annular recess 109 serving to prevent damage to the pointed end of the pendulum when the pendulum is being urged downwardly into the groove 102 as shown in FIGURE 3. Radially outwardly of the groove 102 there is provided an upstanding annular flange 106 serving to limit the degree of inclination of the pendulum with regard to the longitudinal axis of the apparatus, and serving to direct the lower end of the pendulum into the groove 102 when the apparatus is operated, as will be hereinafter described, under extreme degrees of inclination.

Operation of the apparatus may now be described. When the apparatus is positioned in a drill string and the piston 34 is in the position shown in FIGURE 1, the flange 36 of the piston serves to prevent free fluid flow between the interior of the drill string above the apparatus and the passages 20. When fluid pressure is developed within the drill string and applied to the upper surface of the piston 34, the piston will be moved downwardly in the sleeve 26 and, if the apparatus is positioned with its axis extending vertically, the lower end of the plumb bob will enter the sleeve 86 as shown in FIGURE 2 and the piston flange 36 will move downwardly occupying the position shown in FIGURE 2. With the piston 34 in this position fluid will flow from the drill string above the apparatus through the upper portion of the casing 12 to the passages 20 and downwardly through the passages 20 into the drill string below the apparatus.

Thus, it will be evident that during drilling operations the drilling fluid will pass through the apparatus and provide its normal function in the bore hole. Furthermore, so long as the inclination of the bore hole is such that the lower end of the pendulum will enter the sleeve 86, the fluid flow may be interrupted relieving the pressure from the top of the piston 34 permitting the piston to rise from the position shown in FIGURE 2 to the position shown in FIGURE 1 and, thereafter, be reestablished pressing the piston down to the position shown in FIG- URE 2 whereupon the drilling may be resumed. Each such cycle of operation will reaffirm the fact that the inclination of the portion of the bore hole in the vicinity of the instrument does not exceed a predetermined degree of inclination from vertical.

If, on the other hand, the portion of the bore hole containing the instrument (which will be a newly drilled portion) is at an angle exceeding a predetermined angle from vertical and fluid pressure is relieved from the top of the piston, the piston will rise to the position shown in FIGURE 1 but the pendulum will move to a vertical position while the remainder of the instrument is inclined and, if this inclination is such as to bring the point of the lower end 58 of the pendulum outside of the rim of the bevel 100 of the sleeve 86, reestablishment of the pressure on top of the piston 34 depressing the piston will cause the lower end of the bob to move downwardly and ultimately assume a position in the groove 102 such as that shown in FIGURE 3. With the piston in the position as shown in FIGURE 3, the piston flange 36 has not moved downwardly sufliciently to permit the flow of fluid through the upper portion of the casing 12 to the passages 22 therein and, thus, the fluid pumping means provided at the surface of the earth will indicate this blocking condition provided by the apparatus. A surface indication will then occur in the form of a pressure rise and decrease of flow of the pumped fluid, whether liquid or gas.

If the degree of inclination of the apparatus is such that upon operation thereof the lower end 58 of the pendulum comes to rest precisely upon the knife edge 101 forming the uppermost rim of the upper end of the sleeve 86 as shown in FIGURE 5, the sleeve 86 will be depressed by the pendulum as shown in FIGURE 5 until the tapered surface of the end of the pendulum comes into contact with the rim of the groove 102 whereupon the end of the pendulum will be cammed radially inwardly causing the pendulum to slide off the edge 101 and over the conical surface 100 downwardly in to the sleeve 86. The force existing between the end of the pendulum and the knife edge rim 101 of the sleeve 86 under these conditions can not exceed the force provided by the spring 88 and, thus, by proper selection of the spring 88 there can be avoided any damage being caused to the knife edge of the sleeve 86 or to the point of the lower end of the pendulum 56. It will be evident that this is an important consideration when it is considered that it is desirable to indicate limit inclinations of as little as 2 /2 from vertical.

When the apparatus has been operated to provide art indication and is in the position shown in FIGURE 3 with the piston 34 depressed and the lower end of the pendulum in the groove 102 the force acting on the upper surface of the piston 34 will be suflicient to drive the ball 58 of the upper end of the pendulum upwardly past the detent pins 64 by causing expansion of the O-ring 66 and the ball will be in the position shown in FIGURE 3. Downward movement of the piston 34 is limited by contact of one edge of the surface 108 of the upper end of the pendulum body with the under surface of the disc 52. At this time the pressure below the piston will be applied to the bellows 74 but no eflective action thereof occurs. When, thereafter, the pressure on the upper end of the piston 34 is relieved the piston will rise and the action of the pointed ends of the detents under the ball 58 will draw the pendulum upwardly into plane engage ment with the lower surface of the disc 52 (the pressure on the bellows being relieved) and, thus, the pendulumwill be positioned axially of the apparatus as shown in- FIGURE 4 even though the apparatus may be inclinedfrom vertical. With the pendulum in this position fluid pressure may again be applied through the drill string tothe top of the piston 34 whereupon the piston will be depressed with the lower end of the pendulum entering the sleeve 86 and drilling may be resumed.

Upon such depression of the piston, fluid pressure enters sleeve 26 and acts upon the bellows 74 compressing the bellows, moving the cup downwardly and moving the plug 84 downwardly. This downward motion of the plug 84 presses the ball 58 of the pendulum assembly downwardly past the detents 64 and these parts will then occupy the respective positions shown in FIGURE 2. So long as fluid pressure is maintained in the drill string the piston 34 will remain depressed and the parts will remain in the positions shown in FIGURE 2. This permits, after subsequent drilling, a successive operation of the apparatus without removal thereof from the borehole. Such successive operation is accomplished merely by relieving the fluid pressure in the drill string, permitting the piston 34 to rise and then restoring the fluid pressure in the drill string depressing the piston 34. If, at this time, the degree of inclination is not in excess of the predetermined degree as established by the diameterof the rim 101 of the conical bevel in the sleeve 86, the lower end of the pendulum will enter the sleeve and fluid will flow downwardly through the drill string. If, on the other hand, the degree of inclination of the apparatus is in excess of said predetermined degree the lower end of the plumb bob will seat in the groove 102, the parts will assume positions as shown in FIGURE 3 and fluid flow downwardly through the drill string will be prevented by the piston 34.

From the foregoing it will be evident that the apparatus provides for an indication at the surface of the earth of inclination of a bore hole in response to fluid pressure in the bore hole and permits the making of successive indications without substantially interrupting the drilling operation even though each of these indications indicate an excessive degree of inclination.

The indication limit of the assembly may be changed to a minor extent by substituting other sleeves for the sleeve 86 to provide various diameters of the knife edge rim 101 of the conical recess 100 in the upper end thereof. Greater degrees of variation in inclination limit can be obtained by replacing the member 40 and the sleeve 86 by assemblies having sleeves of greater diameters and/ or by changing the length of the plumb bob.

It will be evident that the oil within the sleeve 26 serves to damp the plumb bob and to lubricate and wash the various working parts and that this oil damping in combination with the displaceable sleeve 86, as discussed above in connection with FIGURE 5, serves to provide apparatus which is resistant to damage in both handling and in operation while, at the same time, the knife edge rim 101 and pointed end of the plumb bob serve to provide extremely accurate distinction between allowable and excessive degrees of inclination.

It should also be noted that during drilling operations successive sections of drill pipe are added to the drill string as drilling progresses. With the addition of each section the fluid pressure within the drill string is re lieved while the additional piece of drill pipe is being added. Thus, the apparatus automatically provides an inclination check each time a new piece of drill pipe is added to the drill string while, at the same time, permitting a continuation of drilling even though an excessive inclination is indicated. Under certain conditions and by various techniques, not necessarily described herein, an inclined bore hole can be straightened without removal of the drill string and without the use of special apparatus. Thus, the inclinometer disclosed herein permits a continuation of drilling even after providing an indication of excessive inclination.

The modification of the invention so far described is satisfactory when air or gas is being used as the drilling fluid, but if liquid i used there is the danger of creation of such pressures as may damage the bellows. There will now be described, with reference to FIGURE 6, an alternative form of the appartus which performs the same functions as that previously described but in which the plumb bob is released from the detent pins by a gripping means. In this form of the device there is also provision for sealing the operating elements against the influx of drilling fluid, there being used a floating piston for the maintenance of constant volume during operation. Since the modification shown in FIGURE 6 closely resembles that previously described in detail, it will be described only to the extent of pointing out the differences.

A casing 110, corresponding to casing 12 is provided with similar by-passes 112 for the drilling fluid. A liner 114 is provided with packing 116 through which the piston 118 slides to control by its head 120 the flow of drilling fluid, the piston being urged to its uppermost position by the spring 121. Secured within the liner 114 and packed by packing ring 122 is a cylinder 124 within which there slides the floating piston 126 provided with the packing ring 127.

The plumb bob 128 is supported as in the previously described modification by the ball bearing arrangement 130 and in operation the ball at the upper end of its stern may rise above the pins 132 which are yieldingly pressed inwardly. In the previous modification a bellows arrangement was provided to press the suspending ball of the plumb bob below such pins.

The member 134 slidable in the fixed member 133 and urged upwardly by spring 136 corresponds to the member 86 of the previous modification. In the present case this is provided with slots 138 in which there is located a spring clip member 140 so arranged as to project at opposite ends of a diameter across the bore through the member 134. Cooperating with this is a groove 142 formed about the lower end of the plumb bob.

The operation of the last described modification is essentially similar to that of the earlier modification except in the matter of release of the plumb bob after its support has moved above the pins 132. Following projection of the lower end of the plumb bob through the bore member 134 by the application of pressure, release of pressure will cause the piston 120 to move upwardly under the action of spring 121, and when tins occurs the clip 140 will yieldingly engage within the groove 142 but will provide suflicient restraint to cause the ball at the upper end of the plumb bob to cam outwardly the pins 132 and thus slip beneath them into the normal suspension position on the ball bearing arrangement 130.

As the piston 120 moves upwardly and downwardly relative to the liner 114, the piston 126 follows. such movements to maintain a constant volumetric space for the oil, which in this case, fills the entire region between the piston 120 and the piston 126, thus excluding any drilling fluid from the working parts of the apparatus.

What is claimed is:

1. A fluid pressure responsive inclinometer comprising an elongated casing adapted to be positioned in a drill string in a bore hole, means forming a passage extending longitudinally of said casing, means normally closing off said passage and movable in said casing in response to fluid pressure at one end of said casing to open said passage, means restricting movement of said movable means when the degree of inclination of the casing exceeds a predetermined degree to prevent opening of said passage, and latching means preventing operation of said restricting means during movement of said movable means only after a restricted movement of said movable means whereby said movable means may move to open said passage.

2. A fluid pressure responsive inclinometer comprising an elongated casing adapted to be positioned in a drill string in a bore hole, means forming a passage extending longitudinally of said casing, means normally closing oii said passage and movable in said casing in response to fluid pressure at one end of said casing to open said passage, means including pendulous means restricting movement of said movable means when the degree of inclina tion of the casing exceeds a predetermined degree to prevent opening of said passage, and latching means holding said pendulous means in a non-restricting position during movement of said movable means after a restricted movement of said movable means whereby said movable means may move to open said passage.

3. A fluid pressure responsive inclinometer comprising an elongated casing adapted to be positioned in a drill string in a bore hole, means forming a passage extending longitudinally of said casing, means normally closing off said passage and movable in said casing in response to fluid pressure at one end of said casing to open said passage, means including pendulous means restricting movement of said movable means when the degree of inclination of the casing exceeds a predetermined degree to prevent opening of said passage, latching means holding said pendulous means in an on-center position during movement of said movable means after a restricted movement of said movable means whereby said movable means may move to open said passage, and means releasing said pendulous means from said latching means upon movement of said movable means opening said passage.

4. A fluid pressure responsive inclinometer comprising an elongated casing adapted to be positioned in a drill string in a bore hole, means forming a passage extending longitudinally of said casing, means normally closing off said passage and movable in said casing in response to fluid pressure at one end of said casing to open said passage, said movable means including pendulous means moving to an off-center position upon inclination of the inclinometer, means comprising a receiver for said pendulous means including a central opening receiving said pendulous means and permitting free movement of said pendulous means and said movable means to open said passages when the degree of inclination of said casing does not exceed a predetermined value, said receiver including a surface surrounding said central opening, restricting movement of said pendulous means and said movable means preventing the opening of said passages when the degree of inclination of said casing exceeds said predetermined value, and latching means aligning said pendulous means with said receiver opening only after a restricted movement of said movable means whereby said movable means may move to open said passage.

5. A fluid pressure responsive inclinometer comprising an elongated casing adapted to be positioned in a drill string in a bore hole, means forming a passage extending longitudinally of said casing, means normally closing ofi said passage and movable in said casing in response to fluid pressure at one end of said casing to open said passage, said movable means including pendulous means moving to an off-center position upon inclination of the inclinometer, means comprising a receiver for said pendulous means including a central opening receiving said pendulous means and permitting free movement of said pendulous means and said movable means to open said passages when the degree of inclination of said casing does not exceed a predetermined value, said receiver including a surface surrounding said central opening restricting movement of said pendulous means and said movable means preventing the opening of said passages When the degree of inclination of said casing exceeds said predetermined value, latching means for fixedly holding said pendulous means in alignment with said receiver opening after a restricted movement of said movable means whereby said movable means may move to open said passage, and means releasing said aligning means upon movement of said movable means opening said passage.

6. A fluid pressure responsive inclinometer comprising an elongated casing adapted to be positioned in a drill string in a bore hole, means forming a passage extending longitudinally of said casing, means normally closing off said passage and movable in said casing in response to fluid pressure at one end of said casing to open said passage, said movable means including pendulous means moving to an off-center position upon inclination of the inclinometer, means comprising a receiver for said pendulous means including a central opening receiving said pendulous means and permitting free movement of said pendulous means and said movable means to open said passages when the degree of inclination of said casing does not exceed a predetermined value, said receiver including a surface formed with a substantially V-shaped annular groove sur ounding said central opening receiving said pendulous means and restricting movement of said pendulous means and said movable means preventing the opening of said passages when the degree of inclination of said casing exceeds said predetermined value, saidv receiver including means displacing said pendulous means.

into said opening upon engagement of said pendulous means with the surface of said receiving means forming the boundary between said opening and said groove, and latching means for holding said pendulous means in alignment with said receiver opening after a restricted movement of said movable means whereby said movable means may move to open said passage.

7. A fluid pressure responsive inclinometer as claimed in claim 2 wherein said latching means comprises a detent means cooperable with said pendulous means.

8. A fluid pressure responsive inclinometer as claimed in claim 3 wherein said releasing means comprises means movable in response to the fluid pressure in the casing and cooperable with said pendulous means for actuating the same to the released position thereof.

9. A fluid pressure responsive inclinometer as claimed in claim 3 wherein said pendulous means is connected to said movable means for movement relative thereto be tween the latched and the released positions of said pendulous means.

References Cited in the file of this patent UNITED STATES PATENTS 

